Lock



April 28, 1942- R. B. McFARLANE 2,281,317

' Locx med nw. s, 1940 /NvEA/TUR RUBERT BucHANAN MC FARLAN B Patented Apr. 28, 1942 e' UNITED STATES NT OFFICE LOCK Robert Buchaian McFarlanc, Toronto, Ontario, Canada 5 Claims.

My invention relates to improvements in door locks for automobiles and the like and the object of my invention is to provide a lock mechanism wherein the usual protruding handle may be recessed in the door, and wherein, when the lock is actuated manually to open the door, it is only necessary to work against the resistance of a light compression spring while the bolt is normally held in a protracted position by a heavy compression spring.

A further object of my invention is to provide a door lock which is simple in construction, sturdy, and inexpensive to manufacture.

With the foregoing and other objects in View, as shall hereinafter appear, my invention comprises a door lock constructed and arranged all as hereinafter more particularly described and illustrated in the accompanying drawing, in which:

Figure 1 is a front elevational view of my lock as applied to a fragmentary portion of a steel door; in this view the lock is shown as when the door is closed;

Figure 2 is a front elevational view of my lock as shown in Figure 1, disconnected from the door in order to show the construction of the lock. In this View the latch bolt is shown in its normal protracted position. i

Figure 3 shows the latch bolt and the actuating mechanism in the position which they assume when the handle on the outside of the door is actuated to retract the latch bolt; and

Figure 4 illustrates the position of the parts when the bolt is retracted either by the door jamb during closing of the door, or by the inside handle When opening the door from the inside of the automobile.

Like characters of reference indicate corresponding parts in the different views of the drawmgs.

The lock mechanism is preferably mounted upon a base plate Ill and this plate may be secured to the inner side of the door H in any suitable manner. In the embodiment of my invention illustrated in Figure 1, the outer surface of the door Il is formed with a triangular-shaped recess 12 at the point Where the door handle will be mounted, the door handle being ind'icated by the reference numeral I 3.

The base plate IO is provided with a flange 14 at right angles to the plate and having an orifice therethrough, through which protrudes a latch bolt 15. The latch bolt I 5 normally protrudes from the lock and is retractable by the the shaft 11 passes.

door jamb during the closing of the door and by manually operated means to permit the door to be opened, The'latch bolt 15 is normally held in its protracted position by a heavy compression spring of sufiicient strength to maintain the latch bolt in its protracted position. However, when the latch bolt is retracted manually from the exterior of the door, it is only necessary to work against the resistance of a light compression spring of sufilcient strength to protract the latch bolt and reset the lock mechanism.

For this purpose, the lock includes the following mechanism. Attached to the inner end of the latch bolt 15 is a plate 16 which is provided with a downwardly extending extension Sa. Extending rearwardly from the plate IS and connect'ed thereto in the centre thereof is a shaft 11, the rear end of the shaft passing through and being supported by a bracket IB secured to the base plate IB. The rear end of the shaft l1 is provided with a stop IQ. A second shaft Ha, shorter than shaft l1, has one end passing through the extension lfia of plate 16 with a sliding engagement, this end being provided with a stop 21 which engages against the extension Nia. The other end of the shaft 111'- is connected to a movable stop member 24. The shaft l1a is slidably supported by a pair of brackets 22, 22%, the bracket 22 being located between extension 16a and stop member 24 in such a position that it will not interfere with the inward movement of the latch bolt when it is retracted. The stop member 24 extends transversely across the shaft 11 and is provided with an orifice through which Mounted upon the shaft 11 between the movable stop member 24 and the plate 16 is a heavy compression spring 25.

The stop member 24 is releasably held in its fixed position by means of the following assembly, Pivotally mounted on the stop member 24 is a bell crank lever 26 which has an arm 21 extending in front of the stop member and towards the latch bolt. The forward end of the arm is bent downwardly to engage with a lug 28 projecting from plate Ill. It will be observed that when the arm 21 is in engagement with the lug 28, the stop member 24 is maintained in fixed position. At the rear of the arm 21 is an extension 21a which. after allowing sufficient movement of lever 26 on its fulcrum to lift the arm 21 out of engagement with the lug 28, engages against the member 24 and further pivotal movement of lever 26 on its fulcrum is prevented. The arm 30 of the bell crank lever 26 is approximately at right angles to arm 21 and is operatively connected to the handle l3 by means of rod 3l and arm 32 which is carried on the shaft 33. One end of the rod 3l is connected to the arm 30 by a pivoted bracket 34 and the other end is pivotally connected to the free end of the arm 32. Carried on the rod 3l is a spring 35 which is compressible between a fixed abutment 36 adjacent the arm 30 and the enlarged portion of the rod 3l adjacent the arm 32. One end of the shaft 33 is rotatably supported by the plate l and the other end is supported by a bracket 31 which is mounted on the base plate I0 in such a manner as to be slightly spaced therefrom to allow the arm 32 to move freely. Each end of the shaft 33 is formed with a square recess 38 to receive one of the spindles upon which the handle l3 is mounted.

The usual means is provided for opening the door from the inside and in the present case includes a shaft 40 which is connected to the shaft ll by means of member 4l which has a limited sliding movement on the shaft ll. The member lH4 also carries a shaft 42 Which may be moved into engagement with lever 26, preventing it from being released from engagement with lug 28, and thus lock the door from the inside. By moving the inside handle (not shown) in one direction, the shaft 40 pulls the shaft Il to retract the latch bolt l and by moving the handle in the opposite direction, the shaft 42 is slid under the lever 26 preventing the door being opened by the handle l3.

The operation of the door lock is as follows: In Figure 2, the lock is shown in its normal position and it is assumed that it is holding the door in closed position. To open the door from the outside, the handle |3 is pressed downwardly. The initial movement of the handle causes a pivotal movement of the bell crank lever 26 which raises the arm 21 out of engagement with the lug 28, thereby allowing the stop member 24 to slide freely on the shaft I'l. Continued downward movement of the handle l3 moves the stop member. As pointed out hereinbefore, the shaft l'la is secured, at its rearward end, to the stop member 24. Therefore, any movement of stop member 24 causes a corresponding movement of shaft Il'a. `As stop member 24 is moved rearwardly by movement of the handle l3 through the bellcrank lever 26, the shaft Ha moves a corresponding distance. The stop member 21 on the end of shaft ila engages extension IBa of plate 16 thereby causing a corresponding movement of plate I 6. The rearward movement of plate Hi causes a corresponding rearward movement of shaft ll, thus retracting latch bolt l5 while maintaining the same relative distance between plate IB and stop member 24.

During the opening of the door from the inside, the movement of the various parts of the lock mechanism is much the same as when the door is being closed and the lock bolt actuated by the strike plate. The only difference is that the lock bolt, instead of being pushed to its retracted position, is pulled to its retracted position by the shaft 40 which is connected to the inner handle and the shaft ll.

It will be seen from the foregoing that I have provided a lock mechanism which is simple to construct and easy to operate.

What I claim as new and desire to protect by Letters Patent of the United States is:

1. A door lock comprising in combination a base plate, a main shaft slidably carried by said base plate, a latch bolt on one end of said main shaft, a movable stop member on said shaft, a relatively heavy compressible spring mounted on said shaft between said stop member and a spaced apart abutment secured to said shaft approximate to said latch bolt, said compressible spring normally holding said shaft in latch bolt protracted position, a second shaft having one end slidably carried by said abutment and the other end secured to and actuated by movement of the said movable stop member, means for limiting the movement of said second shaft independently of said abutment, and manually operated means operably connected to said movable stop member, said manually oper-able means including relatively light spring means adapted to return the assembly to its normal latch protracted position, and means for retracting said latch bolt independently of said manually operated means.

2. A door lock comprising in combination a base plate, a main shaft slidably carried by said base plate, a latch bolt on one end of said main shaft, a movable stop member on said shaft, a relatively heavy compressible spring mounted on said shaft between said stop member and a spaced apart abutment secured to said shaft approximate to said latch bolt, said compressible spring normally holding' said shaft in latch bolt protracted position, a second shaft having one end slidably carried by said abutment and the other end secured to and actuated by movement of the said movable stop member, and means for limiting the movement of said second shaft independently of said abutment, and manually operated means operably connected to said movable stop member including a bellcranklever pivotally oonnected to said stop member, one arm of said lever being normally latched over a lug projecting from said base plate and the other arm-being operably connected to an operating handle and relatively light spring means adapted to return the assembly to its normal latch protractedl position, means for limiting the pivotal movement of said lever, and means for retracting said latch bolt independently of said manually operated means.

3. A door lock comprising in combination a base plate, a main shaft slidably carried by said base plate, a latch bolt on one end of said main shaft, a movable stop member on said shaft, a relatively heavy compressible spring mounted on said shaft between said stop member and a spaced apart abutment secured `to said shaft approximate to said latch bolt, said compressible spring normally holding said shaft in latch bolt protracted position, a second shaft having one end slidably carried by said abutment andithe other end secured to and actuated by movement of the said movable stop member, and means for limiting the movement of said second shaft independently of said abutment, and manually operated means operably connected to said movable stop member including a bellcrank lever pivotally connected to said stop member, one arm of said lever being normally latched over a lug projecting from said base plate and the other arm being operably connected to an operating handle and relatively light spring means adapted to return the assembly to` its normal latch protracted position, means for limiting the pivotal movement of said bellcrank lever, and manually actuated means for preventing the pivotal movement of said lever, and means for retracting said latch bolt independently of Said manually operated means, i

4. A door lock comprising in combination a base plate, a main shaft slidably carried by said base plate, a latch bolt on one end of said nain shaft, a movable stop member on said shaft, a relatively heavy compressible spring mounted on said shaft between said stop member and a spaced apart abutment secured to said shaft approximate to said latch bolt, said compressible spring normally holding said shaft in latch bolt protracted position, a second shaft having one end slidably carried by said abutment and the other end secured to and actuated by movement of the said movable stop member, means for limiting the movement of said second shaft independently of said abutment, and manually operated means operably connected to said movable stop member, said manually operable means including relatively light spring means adapted to return the assembly to its normal latch protracted position, and manually actuated locking means acting against said second shaft thereby preventing movement thereof.

5. A door lock comprising in combination a base plate, a main shaft slidably carried by said ing the movement of said second shaft independently of said abutment, and manually operated means operably connected to said movable stop member, said manually operable means including relatively light spring means adapted to return the assembly to its normal latch protracted position and means for retracting said latch bolt Without movement of said stop member including means for retracting the main shaft against the progressively increasing resistance of said relatively heavy compressible spring.

ROBERT B. MCFARLANE. 

